#### Answer

$x=25$

#### Work Step by Step

Step 1. Let x represent one of the unknown quantities.
$x$ = the number
Step 2. Represent other unknown quantities in terms of x.
$0.20x$ = 20% of itself
Step 3. Write an equation in x that models the conditions.
$x-0.20x = 20$
Step 4. Solve the equation and answer the question.
$x-0.20x = 20$
$0.8x=20$
Divide both sides by 0.8:
$x=25$
Step 5. Check the proposed solution in the original wording of the problem.
if $x=25$
$x-0.20x = 20$
$25-0.20(25) = 20$
$25-5=20$
$20=20$-->TRUE